The present invention relates to dispensing apparatus for use in machines for packeting cigarettes and particularly for packeting cigarettes into hinged-lid rigid type cigarette packets.
In known machines of this kind bundles of cigarettes are enclosed in an inner envelope of tin-foil and the envelope is then inserted into an outer, parallel sided cardboard packet.
The hinged-lid rigid type cigarette packet is obtained by a series of folding operations carried out on a substantially rectangular piece of cardboard suitably glued along the areas thereof which come into contact and are stuck together by means of conventional glueing apparatuses of the type, for example, disclosed in our Italian Pat. No. 997,144.
During the transferring steps which follow the glueing operation, particular attention has to be given to ensure that, owing to the elasticity of the material and to the mechanical stresses to which the packets are subjected, the glued portions thereof do not move apart or become displaced. These drawbacks mainly appear on those portions of the packet which are, in the final stages, subjected to the folding operations, and in particular along the side faces of the packet.
It is therefore advisable, for the abovementioned reasons, to subject the individual cigarette packets during transfer thereof to a gauging operation, i.e. each packet has to be inserted into a space which is exactly complementary to the shape of the packet, and to retain the packet in the space for a time long enough to assure proper drying of the glued portions.
By applying heat to the packet the drying time can be shortened. Accordingly, various conventional dispensing apparatuses are provided with a suitably heated channel along which packets are moved and along which each individual packet is kept in its correct position, not only by the walls of said channel, but also by the pressure exerted thereon by the contiguous packets.
A safer operation, however, is provided by those dispensing apparatuses to which further reference will be made hereinafter, of the type in which each packet is advanced intermittently while contained by a rigid compartment and those sides of the compartment adjacent to the sides of the packet are defined by electrically heated plates, which plates are stationary or moved against the packets during each dwell of the intermittent motion.
Due to use of electrically operated means, various problems arise when the motor of the packeting machine and the related dispensing apparatus stop. In this situation, the packets contained in the dispensing apparatus are subjected to a heating action which is excessive relative to that strictly necessary to assure the correct drying. This, obviously, damages the packets as well as their contents. As the electrically heated plates do not cool immediately, simply switching off the electric current is practically useless in avoiding damage to the packets and/or to the cigarettes.